Messages in this thread | | | Subject | Re: [PATCH v4 0/5] Support qcom pinctrl protected pins | From | Andy Shevchenko <> | Date | Mon, 26 Mar 2018 11:39:04 +0300 |
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On Fri, 2018-03-23 at 09:34 -0700, Stephen Boyd wrote: > This patchset proposes a solution to describing the > valid > > pins for a pin controller in a generic way so that > qcom > > platforms can expose the pins that are really > available. > > > > Typically, this has been done by having drivers and > firmware > > descriptions only use pins they know they have access to, and > that > still works now because we no longer read the pin direction > at > > boot. But there are still some userspace drivers and debugfs > facilities > > that don't know what pins are available and attempt to read > everything > > they can. On qcom platforms, this may lead to a system hang, which > isn't > very nice behavior, even if root is the only user that can trigger > it. > > > The proposal is to describe the valid pins and then not allow things > to > cause problems by using the invalid pins. Obviously, the firmware > may > mess this up, so this is mostly a nice to have feature or a safety > net > so that things don't blow up > easily.
FWIW, Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Changes from v3: > * Split out allocation of mask into subroutine > * Moved that allocation to kmalloc_array() > * Updated qcom driver to simplifiy ACPI logic and fix mem leak > > Changes from v2: > * Renamed binding to 'gpio-reserved-ranges' > * Reworked gpiolib patch to not use irqdomains > * Update qcom driver patch to use new valid_mask field > > > Changes from > v1: > > * Pushed into gpiolib-of core under irq valid line > logic > > * Fixed up qcom driver patch to free stuff properly and remove custom > code > * Dropped export patch as it got picked > up > > * Renamed binding to 'reserved-gpio-ranges' > > > Stephen Boyd (5): > dt-bindings: gpio: Add a gpio-reserved-ranges property > gpiolib: Extract mask allocation into subroutine > gpiolib: Change bitmap allocation to kmalloc_array > gpiolib: Support 'gpio-reserved-ranges' property > pinctrl: qcom: Don't allow protected pins to be requested > > .../devicetree/bindings/gpio/gpio.txt | 7 +- > drivers/gpio/gpiolib-of.c | 24 +++++++ > drivers/gpio/gpiolib.c | 66 +++++++++++++++++- > - > drivers/pinctrl/qcom/pinctrl-msm.c | 65 +++++++++++++++++- > include/linux/gpio/driver.h | 16 +++++ > 5 files changed, 167 insertions(+), 11 deletions(-) >
-- Andy Shevchenko <andriy.shevchenko@linux.intel.com> Intel Finland Oy
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